Explore the intricacies of backdoors in software systems through this 33-minute conference talk from GrrCON 2014. Delve into the world of vulnerabilities by design, examining historical backdoors and their creators. Learn about the characteristics of effective backdoors, including examples from the Linux kernel and other notable cases. Analyze the techniques used to implement and conceal backdoors, from simple character removals to more sophisticated methods. Gain insights into the motivations behind intentional vulnerabilities and their potential consequences. Discover how seemingly innocuous coding practices can lead to significant security risks. Enhance your understanding of software security and the importance of thorough code review to identify and prevent backdoors.